This invention relates to a filter made of prisms and which partially transmits or shields light.
Conventional transparent glass plates transmit light through the entire surface thereof. Therefore, when it is employed as a front window or a windshield of a car, the driver is often dazzled by the light of an oncoming car. Furthermore, when it is employed as a plate glass front of a display case which faces the sun-shining outside street, the sun beams are transmitted through the window and fade the articles on display resulting in the deterioration of the commercial value of the articles.
It is an object of the present invention to provide a prism-made filter which can resolve the aforementioned problems which have afflicted conventional glass elements.
It is further an object of the present invention to provide a filter which is applicable to other specific uses.
This invention relates to a filter which is characteried in that two right-angled prisms have their inclined surfaces thereof abutting with each other thus forming quadrilateral filter units and those filter units are stacked and secured one after another forming an elongated filter plate and furthermore a shield means is provided between the stacked surfaces of the filter units whereby the thus produced filter can partially transmit or shield the incoming light.